System and method for preserving inkjet operational status following printer operations that expose inkjets to drying

Abstract

An inkjet printer includes a printhead maintenance station that emits a mist of fluid onto the faceplate of a printhead mated to a receptacle within the printhead maintenance station. A controller is configured to operate one or more nozzles within the receptacle at predetermined time intervals to maintain a film of a fluid mist on the printhead mated to the receptacle. Alternatively, the controller is configured to monitor a humidity level within the receptacle and operate one or more nozzles within the receptacle to maintain the humidity level within a predetermined range. When more than one nozzle is provided in the receptacle of either embodiment, the controller is further configured to operate the nozzles independently of one another.

What is claimed is: 
     
         1 . An inkjet printer comprising:
 at least one printhead module; and   a printhead maintenance station, the printhead maintenance station including:
 a first receptacle, the first receptacle being configured to mate with a faceplate of a first printhead; 
 a first nozzle in the first receptacle, the first nozzle being configured to emit a first fluid mist onto the faceplate mated to the first receptacle; and 
 a controller configured to operate the first nozzle at predetermined time intervals to maintain a film of the first fluid mist on the faceplate mated to the first receptacle. 
   
     
     
         2 . The inkjet printer of  claim 1 , the printhead maintenance station further comprising:
 an actuator operatively connected to the first printhead, the actuator being configured to move the first printhead between a first position where the faceplate of the first printhead does not mate with the first receptacle and a second position where the faceplate of the first printhead mates with the first receptacle; and   the controller is operatively connected to the actuator, the controller being further configured to:
 detect a condition indicative of maintenance needed for the first printhead; and 
 operate the actuator to move the first printhead to the second position. 
   
     
     
         3 . The inkjet printer of  claim 2  wherein the condition is a number of inoperative inkjets in the first printhead. 
     
     
         4 . The inkjet printer of  claim 2  wherein the condition is an image metric that is outside a predetermined threshold. 
     
     
         5 . The inkjet printer of  claim 2  wherein the condition is a number of inkjet images printed by the first printhead. 
     
     
         6 . The inkjet printer of  claim 2  wherein the condition is an expiration of a time interval between printhead maintenance operations. 
     
     
         7 . The inkjet printer of  claim 2  wherein the condition is a number of ink images printed within a predetermined period of time. 
     
     
         8 . The inkjet printer of  claim 1  further comprising:
 a second nozzle in the first receptacle, the second nozzle in the first receptacle being configured to emit a second fluid mist onto the faceplate of the first printhead mated to the first receptacle; and 
 a controller being configured to operate the second nozzle in the first receptacle independently of the first nozzle in the first receptacle. 
 
     
     
         9 . The inkjet printer of  claim 1 , the printhead maintenance station further comprising:
 a second receptacle, the second receptacle being configured to mate with a faceplate of a second printhead;   a first nozzle in the second receptacle, the first nozzle in the second receptacle being configured to emit a first fluid mist onto the faceplate mated to the second receptacle; and   the controller being further configured to operate the first nozzle in the second receptacle at the predetermined time intervals independently of the first nozzle in the first receptacle.   
     
     
         10 . The inkjet printer of  claim 9 , the printhead maintenance station further comprising:
 a second nozzle in the second receptacle, the second nozzle in the second receptacle being configured to emit a second fluid mist onto the faceplate of the printhead mated to the second receptacle; and   the controller being further configured to operate the second nozzle in the second receptacle at the predetermined time intervals independently of the first nozzle in the second receptacle.   
     
     
         11 . An inkjet printer comprising:
 at least one printhead module; and   a printhead maintenance station having:
 a first receptacle, the first receptacle being configured to mate with a faceplate of a first printhead; 
 a first nozzle in the first receptacle, the first nozzle being configured to emit a first fluid mist onto the faceplate mated to the first receptacle; 
 a first humidity sensor within the first receptacle, the first humidity sensor being configured to generate a signal corresponding to a humidity level within the first receptacle; and 
 a controller operatively connected to the first humidity sensor, the controller being configured to:
 compare the signal generated by the first humidity sensor to a predetermined range of humidity levels that correspond to a drying rate of a liquid ejected by the first printhead; and 
 supply a solvent to the first nozzle to maintain the humidity level within the first receptacle within the predetermined range of humidity levels that correspond to a drying rate of a liquid ejected by the first printhead. 
 
   
     
     
         12 . The inkjet printer of  claim 11 , the printhead maintenance station further comprising:
 a second receptacle, the second receptacle being configured to mate with a faceplate of a second printhead;   a first nozzle in the second receptacle, the first nozzle in the second receptacle being configured to emit a first fluid mist onto the faceplate mated to the second receptacle;   a second humidity sensor within the second receptacle, the second humidity sensor being configured to generate a signal corresponding to a humidity level within the second receptacle; and   the controller operatively connected to the second humidity sensor, the controller being configured to:
 compare the signal generated by the second humidity sensor to a predetermined range of humidity levels that correspond to a drying rate of a liquid ejected by the second printhead; and 
 supply a solvent to the first nozzle in the second receptacle to maintain the humidity level within the second receptacle within the predetermined range of humidity levels that correspond to a drying rate of a liquid ejected by the second printhead. 
   
     
     
         13 . The inkjet printer of  claim 12 , the printhead maintenance station further comprising:
 an actuator operatively connected to the first printhead, the actuator being configured to move the first printhead between a first position where the faceplate of the first printhead does not mate with the first receptacle and a second position where the faceplate of the first printhead mates with the first receptacle; and   the controller is operatively connected to the actuator, the controller being further configured to:
 detect a condition indicative of maintenance needed for the first printhead; and 
 operate the actuator to move the first printhead to the second position. 
   
     
     
         14 . The inkjet printer of  claim 13  wherein the condition is one of a number of inoperative inkjets in the first printhead, an image metric that is outside a predetermined threshold, a number of inkjet images printed by the first printhead, an expiration of a time interval between printhead maintenance operations, a number of ink images printed within a predetermined period of time. 
     
     
         15 . A method of operating an inkjet printer comprising:
 operating a first nozzle in a first receptacle at predetermined time intervals to maintain a film of a first fluid mist on a faceplate of a first printhead mated to the first receptacle.   
     
     
         16 . The method of  claim 15  further comprising:
 detecting a condition indicative of maintenance needed for the first printhead; and 
 operating an actuator to move the first printhead from a first position where the faceplate of the first printhead does not mate with the first receptacle and a second position where the faceplate of the first printhead mates with the first receptacle to the second position. 
 
     
     
         17 . The method of  claim 16  wherein the condition is one of a number of inoperative inkjets in the first printhead, an image metric that is outside a predetermined threshold, a number of inkjet images printed by the first printhead, an expiration of a time interval between printhead maintenance operations, and a number of ink images printed within a predetermined period of time. 
     
     
         18 . The method of  claim 15  further comprising:
 operating a second nozzle in the first receptacle independently of the first nozzle in the first receptacle. 
 
     
     
         19 . The method of  claim 15  further comprising:
 operating a first nozzle in a second receptacle at the predetermined time intervals to maintain a film of a second fluid mist on a faceplate of a second printhead mated to the second receptacle independently of the first nozzle in the first receptacle. 
 
     
     
         20 . The method of  claim 19  further comprising:
 operating a second nozzle in the second receptacle at the predetermined time intervals independently of the first nozzle in the second receptacle.